The term "upload" has several meanings depending on its context. In general, it refers to the process of transferring data from a source computer or device to another system or server over the internet. This could be done for various purposes such as sharing files, backing up data, or making content available online.
In everyday language, "upload" can also mean adding new information or data to an existing system or database. For example, when you add a photo to your social media account, it is said that you are uploading the file from your device to their server.